import ceylon.test { ... }
import ceylon.math.integer { ... }

test void testIntSumProduct() {
    print("Integer.sum");
    assertEquals { 
        expected = 0;
        actual=sum {};
    };
    assertEquals { 
        expected = 6; 
        actual=sum { 1, 2, 3 };
    };
    print("Integer.product");
    assertEquals { 
        expected = 1; 
        actual=product {};
    };
    assertEquals { 
        expected = 6; 
        actual=product { 1, 2, 3 };
    };
}